Electric time switch



June 30, 1925. 1,544,333

W. B. MARKS ELECTRIC TIME SWITCH 36 Filed March 1', 1924 BY w ORNEY Patented June 30, 1925.

v WIIzIgIAM B. MARKS, OF WATER/BURY, CONNECTICUT.

ELEGIRIC TIME SWITCH.

. lpplioltionfi led March 1, 1924. Serial No. 696,185.

To all whom it may come-m;

Be it known that I, Woman 13. LIARKS, a citizen ofthe United States,-an(l a resident of Waterbury, county'of New Haven, and-State of Connecticut, have inve t d certain, new and usel'ul Improvements in Electric Time Switches, of whichthe following is a specification.

This invention relates to electric tinieswitchesand more particularly to a timeswitch for automatically shutting off the current from eleetrielighting systems, electrio motors, etc. ,nfter anydesiredpredctcrminedperiod of use.

One object of this invention is to provide anclectric time'switch of the above naturevincluding a'central. shaft having a radial contact member which is adapted to rotate within the successivelayers ofa stationazy spiral contact member.

A urther object is to provide a timeswitch of the above nature adapted to be operated by clock work, the latter'being entirely insulated from thepath of the electrio current.

A further object is .toprovide adevice of-the above nature which will be simple, compact, inexpensive to manufacture, easy to manipulate, and very eflieient and durable in use. I

W'ith these and other objects in view,

there have been illustrated on the accompanyingdrawing two forms in which the invention may be conveniently embodied in practice.

Fi 1 represents a perspective view of the first. fornroftimeswitch as it appears when completely assembled.

Fig. 2 is a diagrammatic view of the wiring circuit of which the electric timeswitoh forms a part.

Fig. 3 is aperspective view showing the component parts of the switch mechanism in separated relation.

Fig. .4 is a top View of theswitch mecbanism as it appears when the casing and operating handle have been removed.

Fig. 5 is a top VicWofn modifiod' form of time-switch also cmbodyingthe principles of the invention.

Referring now to-the drawingsin which like reference numeralsxionote corresponding parts throughout the several views,.tho numeral 1O indicates a rectangular support preferably of wood, said support having secured thereto, by screws, abuse 11 of the shape of a circular disc.

sion is made of a cylindrical, cup-shaped casing 15, sa d cusingbemg 'lllvertedwhen in use, and having a pair of. opposed notches 16 on its bottom edge to receive a pair of conductors l7 and 18. The conductor 17 leads directly toone wire 19 of a source of current, asv clearly shown inthe diagram of Fig. 2. The conductor 18 leads .to'u binding post 20 of a lumpsocket 21,01 to any other electric power consuming unit, such as a bank oflamps, as shown in Fig A .wire 22 leads from the other bindmg post 23 of the lump socket 2101 other.

unit to the second wire 24 of the source of current.

The top of the, casing :15 .is provided with a dial 25, having a scale graduated in any suitable manner, as into minutes as shown. An operating arm 26 and .a pointer 27 are mounted to rotate above saicldial 25. The arm26'is provided witha knob.

28 at'itsouter. end by means of which the pointer, which is rigidly connectedat any desired-angle ,to the arm 26, may be rotated to set the pointer at any position upontlie dial.

The arm 26 and the pointer 27 are detachahly secured on the endof a hollow collar member 29 by means ofa screw 30 threaded into the topof said collar member. Thecollur member 29is adapted to extend down through a central aperaturc 30' in the top of the casing 25, and is'pro videdsat its lower end 31 with a tapped hole 31 adapted to screw upon the upper threaded portion 3250f=a central main shaft 33 mounted in suitable bearings inthe upper and lower plates 13 and 14,'previously mentioned. The central shaft 33 is adapted to be driven by a suitable spring motor and gearing not shown, and the gearing-is preferably so arranged that thepointer 27 will make one revolution per hour.

' Rigidly momtcd on the central shaft 33 above the plate 13 is a stationary flat insulating ring 3%, said ring Set being secured to the plate 13 in any suitable manner, as by screws adapted to lit in screw holes 35. The ring 3% is provided with a large aper ture at its center and has a radial slot 3 extemling from its outer perimeter part way to the central aperture thereof. As clear 1y shown in Figs. 3 and :i, one side of the slot 36 is cut oil square while the other side is tapered to form a wedge portion 37, for a purpose to be hereinafter described.

In order to provide a stationary electrical contact, a narrow metallic ring 38 is provided flush with the inner circumference of the aperture in the insulating ring 3%, said metallic ring being secured to said insulating ring by means of rivets 39. The metallic ring 38 has a downwardly extend ing section l0 at one side to which is connected an elbow member at having a depending binding terminal located outside of the clock framework inside of the casing 15. The terminal 42 is adapted to be connected to the conductor 17 previously mentioned, as by a binding screw 43.

A movable metallic contact ring-member is located on the central shaft 33 above the stationary metallic ring 38, said movable ring-member it being connected, as by rivets 4:5 to a disc at; of insulating material. The disc 46 in turn is adapted to be secured at its center to a circular plate a7, as by rivets 48, said plate l-T surrounding the central shaft 33 and being seated on a shoulder formed at the bottom of the threaded section 32. A washer if) is preferably located im mediately above said plate 47. The movable contact ring 4st is provided on one side with a short arm or lug 50 adapted to lie in electrical contact with the stationary ring 58 at all times. The movable contact ring 4% is also provided at a point directly opposite the lug 50, with a resilient long arni 51 having a raised section 52, which is arched upwardly to bridge over the stationary contact ring 38 so as to avoid a short circuit. The outer extremity of the long arm 51 lies in the plane of the ring stat and is adapted to press down upon and electrically engage between the layers of a spiral coil 53.

The spiral coil 58 which is made of flat strip natal, may have any desired number of turns according to the length of time the lamp or other power-consuming device is to be used. Normally, the faces of adjacent sections of the coil are adapted to lie in flat contact with one another. The upper extremity 5 1 of the spiral coil 53 is free, while the lower end thereof is bent reversely upon itself at around the wedge portion 3T of the insulating disc 3i upon which the spiral coil rests. The lower end of the spiral coil 53 is provided with a depending lug 56 located outside the framework of the clock, and being spaced about 45 degrees from the binding terminal l2. The lug 56 is adapted to be connected by means of a binding screw 57 to the conducting wire 18, previously mentioned.

Directly above its reverscly bent lower end the spiral coil 53 is provided with a flat horizontal bent-over portion 57, which is adapted to lie in the plane of the lower stretch of the coil. By means of this construction, when the clock is unwinding, the outer extremity of the long arm 51 of the movable ring it will gradually pass downwardly between the successive layers of the coil 5! and will then ride horizontally upon the flat section 57 until it reaches its edge, whereupon it will suddenly drop into the slot 36, by reason of its resiliency, instantly shutting oil the flow of current.

While the adjacent layers of the spiral coil are shown separated in Fig. 2}, for clearness, it will be understood that said layers will normally lie in contact substantially throughout the entire length of the coil.

In operation, when it is desired to set the time-switch to operate in a period of time less than one hour, the handle 20 will be rotated so as to move the pointer QT around the dial in a clockwise direction until the pointer is t'ipposite the proper scale-reading which in this case will be something less than til) minutes. \Vhen, however, the period of time is greater than one hour, the operator will rotate the handle 26 in a clockwise direction, one revolution for each hour, and will then continue to rotate the pointer an additional distance, as described above, to take care of the additional minutes.

One advantage of this invention lies in the fact that the shaft for operating the time-switch is not limited to a single revolution as was the case with former timeswitches, but may make a plurality of revolutions,-the number depending on the number of turns in the spiral coil.

By means of this construction, it results that the present time-switch may be very accurately adjusted, even down to a fraction of a minute, whereas former types of timeswitches could only be roughly adjusted to fractions of an hour.

In the operation of the present invention, when it is desired to set the time-switch. the handle 26 will be turned in a clockwise direction to the desired point, as already described. During this operation, the extremity of the long arm 51 will ride over the curved cam surface of the lower end of the coil 53 under the flat portion 57. During the unwinding, the clock-work mechanism will cause the shaft 33 and its associated long arm 51 and pointer 27 to rotate in a counter-clockwise direction until lilo the long-arm 51 has again opened the circuit in the manner described above.

In some cases, itmaybedesired to shut off the power beforethe time for whichthe time-switch has been set. For this purpose,

the modified form of device shown in Fig;

5 may be employed. 7 This form of timeswitch is similar to that shown in Fig. 2, but the terminal 42 of the stationary contact ring 38 has a horizontal portion 58 which extends out radially through a slot in the casing 15. The portion 58 forms one terminal of a manually-operated switch, which is operated by a bell crank lever 59 pivoted upon a pint-2 located on a metallic strip (it), secured to the support 10. The strip 60 has a screw 61 at its outer end to serve as a binding pos" for the conducting wire 17. The lever 59 isprovided with a knob 63 at its outer end so that it any be manipulated to swing the lever about its axis when it is desired to open the circuit independently of the time-switch mechanism.

\Vhile there have been disclosed in this specification two forms in which the invention may be embodied, it is to be understood that these forms are shown for the purpose of illustration only, and that the invention is not to be limited to the specilic disclosures but may be modified and embodied in various other forms without departing from its spirit. In short, the invention includes all the modifications and embodiments coming within the scope of the following claims.

-Having thus fully described the invention, what is claimed as new, and for which it is desired to secure Letters Patent, is:

1. In an electric time-switch, a clockwork mechanism, a stationary contact disc forming one terminal of said switch, a coiled strip of metal having overlapping layers, said strip being insulated from said stationary contact disc and forming the other terminal of said switch, a rotary metallic member connecting said disc and said strip and capable of rotating in contact with said strip for more than 360 degrees, said connecting member being driven by said clockwork, and the circuit being broken when said connecting member passes beyond the end of said strip.

2. In an electric time-switch, a stationary contact disc electrically connected to one terminal of a source of current, a spiral strip concentric with said disc and connected to a power consuming device said strip having a plurality of overlapping layers, a motor-driven metallic connecting member having :1 lug in contact with said disc, said connecting member having an arm adapted to successively pass over the layers of said strip, said circuit being broken when the arm of said connecting member passes over the extremity of said strip.

3. In an electric time-switch, a stationary contact disc electrically connected to one terminal of a souree'of current, a coiled strip having overlapping layers, said strip being concentric with said disc and connected to a power consuming device, a n'iotor-driven connecting member having :1 lug on one side in contactwithsaid disc, said connecting member having an arm opposite said lug lying in contact with said strip, said circuit being broken when the arm of said connecting member passes over the extremity of said strip.

4.. In an electric time switch, a stationary, contact disc electrically connected to one terminal of a source of current, a spiral strip concentric with said-disc and connected to a power consuming device, a motor-driven connectingmember having a lug in contact with said disc, said connecting member being pivoted on an axis within said disc, having an arm bridged over saiddisc and adapted to pass between two adjacent. layers ofsaid strip, said circuit being broken when the arm of said connecting member passes over the extremity of said strip.

5. In an electric time-switch, a clockwork frame, a stationary metallic disc secured to said frame and insulated therefrom, said disc forming one terminal of the switch, a helical strip having more than one turn surrounding said disc and forming the other terminal of the switch, a main shaft driven by said clockwork, a. connecting member mounted on said main shaft and insulated therefrom, said COI'IIIQOtlllg member electrically engaging said disc and said slrip,'

said-switch being automatically opened by said clockwork when said connecting member becomes disengaged with the end of said frame.

6. In an electric time-switch, a clockwork mechanism, a stationary contact disc forming one terminal of said switch, a spiral strip having a total angle of greater than 360 degrees insulated from said stationary contact disc and forming the other terminal of said switch, a rotary member connecting said disc and said strip, said connecting member being driven by said clockwork, the circuit being broken when said connecting member passes beyond the end of said spiral strip, a casing having a dial enclosing said mechanism, and a setting and indicating handle located above said dial outside said casing the switch being capable of being set so as to cause said handle to rotate around said dial more than 360 degrees.

7. In an electric time-switch, a clockwork mechanism a stationary contact disc forming one terminal of said switch, a spiral strip insulated from said station contact disc and forming the other terminal of said switch, a rotary member connecting said disc IOU and said strip, said connecting member being driven by said clockwork, the circuit being broken when said connecting member passes beyond the end of said spiral strip, a casing having a dial enclosing said mechaanisni, and a setting and indicating handle located above said dial outside said casing, said handle behrg;- mounted to rotate with said rotary member.

5. In an electric time-switch, a clockwork mecl'ianism, a staiii'marv c intact disc forming one terminal oi said switch, a. spiral strip having overlapping sections insulated "from said station-a" contact disc and forming the other terminal of said switch, a rotar member connecting said disc and said strip, said connecting member being driven by said clockwork. the circuit being broken when said connecting member passes beyond the end of said spiral strip, a casing having a dial enclosing said mechanism, a setting and iudiatin handle lo ated above said dial outside said casing.

S), in an electric timeswitch, a support,

a base on said support, a clockwork frame on said base, an insulating rin secured to the top of said frame, a terminal at the ccnter of said ring, a helical strip terminal at the periphery of said ring, said ring having a slot in its edge, one end of said slot being curved to form a am or wedge, said clockwork havinga main shaft at the center of said ring, and a connectinc member on said shaft adapted to electrically engage said terminal and said strip.

10. In an electric time switch, a rotary contact member. a motor for driving said IOttl'l') member. a stationam contact member consisting of a helical metal strip havinc overlapping layers, wherelrv the switch may be set to cause the rotary member to traverse more than one turn of said strip, and in ans to cause the circuit through said switch to open when the rotary member pa s beyond one end of said strip.

in testimony whereof. I have atliXcd in} izigg nature to this specification.

WlLLlAMl ll. A lthfi. 

